Heat motor



May 18, 1937. L. M. PERsoNs 2,080,576

HEAT MOTOR Filed Aug. 13, 1935 Patented May 18, 1937 UNITED STATES ,QFFICE HEAT MOTOR Lawrence M. Persons, Des Moines, Iowa, assignor to Penn Electric Switch Go.,- D1es Moines, Iowa,

a corporation of Iowa An object of my present invention is to provide a liquid type heat motor of simple, durable and inexpensive construction.

A further object is to provide a heat motor with a means to retain it against collapse when a thermal balance is reached, after volatilizing a volatile fluid in a boiler of the heat motor, the

heat motor, however, being quickly collapsible,

due to condensation of the vapor .therewithin when heating means for the volatile fluid is deenergized.

A further object is to provide. a-kheat motor, comprising a boiler and an expansible andcontractible vessel connected together'by a partition, a thermal balance chamber and a relatively small tubular connection which discourages transmission of heat from the boiler to the expansible vessel.

A further object is to provide in connection with the boiler, a heat radiator to further discourage the transmission of heat fromthe boiler to the vessel.

Another object is to provide a readily manufactured boiler construction for a liquid type heat motor, and one which, duetoits inherent construction, causes quick collapse of the expanded vessel when the heating means is 'de-energized, yet prevents any accidental collapsing of the bellows caused by currents of air striking it and condensing the fluid therein.

With these and other ojects in view, my invention consists in the construction, arrangement and combination of the various. parts'of my-heat motor, whereby the objects contemplated are attained, as hereinaftermore fully, set forth, pointed out in my claims, and illustrated inthe accompanying-drawing, in which:

Figure 1 is a side elevation, partly in section of a heat motor embodying my invention.

Figure 2 is a plan view of the same.

Figure 3 is a diagrammatic view, showing the heat motor expanded; and

Figure 4 is a similar, diagrammatic view showing it partly collapsed.

3 On the accompanying drawing, I have used the reference numeral It to indicate a base. An expansible and contractible vessel, such as the bellows I2, is mounted thereon and sealed relative thereto.

50 On the head of the bellows, perforated ears M are illustrated for connection with any device to be controlled by the heat motor. The interior of the bellows I2 is connected by a passageway 16 in the base I!) with a stand tube l8. Mounted on the stand tube and communicating therewith is a bellows.

whereupon a thermal balance is reached-as the saucer-like element 22 constituting a thermal balance chamber. The upper edge'Z lthereof is spun-over the edge of a disc 5%, which 'disc has atwo-Way perforation or orifice 28 therethrough, preferably located off-center; '7

A boiler 30 is 'connected with the-periphery of the chamber 22, the parts i8, 22, 2t and wall being sealed relative to each other by soldering or the like. Wound 0n the boiler 30 is an electric heating element 32 and the boiler isprovided with a heat radiating skirt'tfi. Secured to the skirt 3% is a sheetjof metal 36, the manner of securing being illustrated as rivets 38. The sheet of metal 36 acts as a further heat dissipating radiator for 15 the skirt as, as-it exposes additional surface to the atmosphere," and ispreferably made of a metal ofquick conducting composition such as copper or aluminum.

Practical operation In the operation of my heat motor, the heating'felement'f32 is energized for the purpose or" heating the'boiler 3E3 and'vaporizing a portion of the volatile liquid it], which fills the boiler and The vapor accumulated depresses the liquid downwardly through-the two-way'orifice 28to approximatelythepo-sitionshown in Figure 3,

further heat condu'cted'by the boiler fit from the heating element'SZ is dissipated by thevskirt 34 and the radiatorIiifi to atmosphereinstead of being conducted by the element'22 to the liquid.

.The liquid level shown in Figure 3 is not fixed, as it maybe evenrdown in the tubular element 1 8,

butnth e parts are designed so that it is at least below the partition 26.

When the thermal balance is reached, currents of air or other variable factors can cause slight contraction and expansion of the bellows I2, which, of course, will raise or lower the level of the liquid, but since the level is within the chamber 22, which has substantial area, the actual change in level is very slight. A slight change only is desirable because a change of considerable extent as would occur in a passage of small cross sectional area which would cause excessive cooling of the boiler by a rapid rise of liquid level in such a passage and consequent condensation of the vapors and thereby collapse of the bellows at a time when the heating element 32 is energized.

On the return of the liquid, however, due to deenergization of the heating element and 001- 55 lapse of the bellows l2 to its original position, it is desirable that it quickly collapse and this is done by providing the two-way orifice 28 in the partition 26 to confine the returning fluid to a jet, indicated at 40a in Figure 4, so that it is sprayed within the boiler and against the walls thereof to cause quick cooling of the walls and thereby quick condensation of the vapors therein.

By my construction as illustrated, the thermalbalanced position of Figure 3 can be retained indefinitely with the heating element 32 energized, yet quick collapsing of the bellows is insured by the spray action upon return of the liquid as shown in Figure 4.

The radiators 34 and 36 serve the purpose of preventing excessive heat transmission to the chamber wall 22, thus preventing excessive vapor accumulation and consequent excessive expansion of the bellows I2.

I locate the orifice 28 off-center relative to the boiler as I have found that when centrally located, the spray 40a, upon striking the upper wall of the boiler, makes considerable noisea drum eifect is obtained. When mounted off-center, however, the action is quieted to a considerable extent.

Changes may be made in the arrangement and construction of the various parts of my heat motor, without departing from the real spirit and purpose of my invention, and it is my intention to cover by my claims, any modified forms of structure or use of mechanical equivalents, which may be reasonably included within their scope.

I claim as my invention:

1. In a heat motor, an expansible and contractible vessel, a boiler in communication therewith, a volatile fluid in said vessel and boiler, means for heating said boiler to effect vaporization of a portion of said fluid and thereby expansion of said vessel, and means for controlling the expansion and contraction of said vessel comprising a chamber between said boiler and vessel of substantial area whereby to provide but small liquid level change upon the liquid being depressed to a thermally-balanced position therein and the volume thereof subsequently changing, due to slight temperature changes, and a partition having a small two-way orifice between said chamber and boiler through which the returning liquid is sprayed to within said boiler to quickly condense vapor therein upon said heating means becoming inoperative and the level of the liquid thereafter rising to said partition.

2. A heat motor comprising an expansible and contractible vessel, a boiler in communication therewith, volatile fluid in said vessel and boiler, means for heating said boiler to effect vaporization of a portion of said fluid and thereby ex pansion of said vessel, and means for controlling the expansion and contraction of said vessel comprising a chamber of substantial area which provides communication between said boiler and vessel whereby to provide but small liquid level change upon the liquid being depressed to a thermally-balanced pcsition therein and the volume thereof subsequently changing due to.

slight temperature changes and a partition having a small two-way orifice between said chamber and boiler through which the returning liquid is sprayed to within said boiler for quickly condensing the vapors therein upon said heating means becoming inoperative, said orifice being located eccentrically relative to said boiler.

3. In a heat motor, an expansible and contractible vessel, a boiler in communication therewith, a volatile fluid in said vessel and boiler, means for heating said boiler to effect vaporization of a portion of said fluid and thereby expansion of said vessel, and means for controlling the expansion and contraction of said vessel, comprising a chamber between said boiler and vessel and a partition between said chamber and boiler provided with a two-way orifice for spraying returning liquid into said boiler, quickly, to condense any vapor there present, said chamber being located in position requiring the level of said liquid when depressed by operation of said heating means to be located therein, a reduced connection from the boiler to the vessel, and a thin heat radiating member connected with said boiler at a point between it and said chamber and having both surfaces thereof in contact with the surrounding air to radiate heat from the boiler to the air before it is received by said chamber and said reduced connection.

4. In a heat motor, an expansible and contractible vessel, a boiler in communication therewith, a volatile fluid in said vessel and boiler, means for heating of said boiler to efiect vaporization of a portion of said fluid and thereby expansion of said vessel and means for controlling the expansion and contraction of said vessel comprising a chamber between said boiler and vessel and a partition between said chamber and boiler provided with a two-Way orifice for spraying returning liquid therein, said chamber being located in position requiring the level of said liquid when depressed by operation of said heating means to be located therein and a reduced connection between said chamber and vessel to reduce heat conduction from the boiler to the vessel.

LAWRENCE M. PERSONS. 

